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Discussion Starter #1
In planning my Scout 2 project out (before the parts accumulation state begins), I've been mulling over my tranny options. I'm really leaning towards using an Isuzu trans. No darn adapters to deal with, and it's internal gearing is already designed to work with the engine's powerband needs. So the only thing left is to get the transfer case to bolt up. Unless the main body length is too long, of course. :confused:

In comes a guy I know. He builds his own "Creeper box". They typically go behind the Chrysler/IH 727 or the T-18/19, and mate to either the Dana 20 or 300's. The box measures only 5 1/2" long, so it's compatible with short wheelbase apps. Anyway, I saw him breifly yesterday and we discussed the ability to use this box on other transmissions. He said that if he had the dimentions off the back of the trans and the output shaft length, diameter and spline count, he could tell me if he could get it to bolt up.

And ulitmately, we aren't limited to just those two transfer cases either. I'm sure he could come up with one to adapt most any case to your trans. He doesn't get alot of call for them (from what I know), so they are all hand made from patterns he developed. So I thought I'd gather more info and go down there with more in hand than an idea.

So here's where you guys come in. Does anyone have that info readily available, or am I just gonna have to spend a few hours at my Isuzu wrecking yard with a tape measure and a set of calipers?

Thanks everyone! :)
 

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I have often wondered if there is a way to do a divorce aDana 300? ( anyone know)

I years ago when AA made an adpater to divorce the model 20 Dana for mini trucks.. datsun and toyota.
THey used a short shaft to the aa-mount/Dana20 and it had it's own t-case base so you could throw a t-case bracket on easily and the 20 was supported by that. So yes IIRC a Dana 20 divorced case adapter might still be around .
They were used in the early 70s.
IMO I think the Dana 300 would be much stronger if built right and theres some aftermarket lower gears if you wanted.

Here is another option and Toyota builds a strong case...
http://images.google.com/imgres?img...?q=+divorced+case+adapter&svnum=10&um=1&hl=en

I think the Izuzu manual trans would be killer... go fo it.
 

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I have two Isuzu boxes (MSA-5P from late 80's and MSA-5G from early 90's), both have different output shaft diameters and spline counts.

So I'd suggest finding a box and measuring it up. Pulling the output flange and sending that to your mate will give him all the information he needs.
I have a stick post above with different boxes and their gear ratios, it'd pay to check that before you hand over the cash for a gearbox as ratios vary widely.

One other point, it seems that all Isuzu MSA gear boxes and even MSB boxes have the same rear housing bolt pattern.
 

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Discussion Starter #5
Yeah, it looks like I'm gonna have to do some yard time. Only thing that sucks about that is that the best source around here (www.fmitrucks.com) is about 50 miles from me. Oh well, that's why I have the diesel Benzo. LOL!

And yes, the Dana 300 is a likely canidate, as the 20 is geetting hard to find (and find parts for, according to those I have asked). I will certainly be upgrading, as I'm not into repairing carnage or waiting for parts. I'm into overbuilding to prevent such problems. Although my 20 has served me well and never failed on me. Also, I'm also not opposed to a Toyota case or trans for that matter, I know they build stout stuff. It's just gotta be a passenger side drop and gear driven. No chain junk for me.

Good news about the tailshaft housing! Now about all we have to worry about is that output shaft. As long as we can get (make, adapt, whatever) a gear to go on that shaft that works with his set-up, we may have a winner! I still have to think about overall length, but we won't know about that until I can measure some trannies. Unless I can talk Dougal into crawling under a truck? :rasta:

I also checked out the gearbox info Dougal posted. Great stuff. That will help me greatly on deciding which box will work best. When the time comes I'll be heating up the 'ol calculator, that's for sure. BTW, are these clutches activated by cable pull or hydraulic slave cylinder?
 

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No crawling under the truck for me, it's in pieces and scattered throughout my garage.

I'm halfway through a gearbox swap, the swap is from the earlier MSA-5P to a lter MSA-5G with a better ratio spread. The holdup at the moment is waiting for the new output shaft to be made.

Have you considered an LT230 landrover transfer box? Both outputs are on the RHS of the vehicle (passenger side for you, driver side for me), gear driven and quite possibly the toughest thing landrover ever made.
Full time 4wd with a manual difflock, low range is 3.something, high range is between 1:1 and 1.6:1 depending on the source of the box.

The kicker is I already have all the shafts and adaptors designed up to make it fit an Isuzu box.

Clutches are all hydraulic.
 

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Discussion Starter #7
Have you considered an LT230 landrover transfer box? Both outputs are on the RHS of the vehicle (passenger side for you, driver side for me), gear driven and quite possibly the toughest thing landrover ever made. Full time 4wd with a manual difflock, low range is 3.something, high range is between 1:1 and 1.6:1 depending on the source of the box.
I think that since the Dana 300 is so widly available here that I should go with that. The two problems I see with the Rover box is the ofset rear driveshaft and the full time feature. This is gonna be a 95% street driven truck, so the full time will be a disadvantage. Besides, if for some reason it fails while traveling, finding a Dana 300 (or related parts) should be about as easy as finding a McDonalds. And they came in the last year of the Scout, 1980, so no custom work to fit it (other than the crawler box of course).

I'll be planning a wrecking yard play day here before too long. I'll see what I can find out then. In the meantime, the hardest thing is staying focused on completing house projects so that I can have more time on the Scout when I do get to work on it. :grinpimp:
 
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